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not sure what engine your refering to but its unlikely youll be able to cut any in because of the inlet design. but besides that i dont think it would do any good. usually on the case reed design, the reed block dumps right into the crankcase area with little obstruction. cylinder reed typically has dividers and such partially blocking the inlet which reduces its area so boyesen ports can be helpful. i think also the boyesen can offer some assistance for the rear boost port up the back of the cylinder on a cylinder reed design. case reed has a stand alone boost port that needs no assistance and there should be little or no obstruction through the inlet area. so i would say even if you could cut in some extra ports they wouldnt do any good but then again ive never tried it

Vendor

You probably don’t have room but a good even array of boost / transfer ports is good. If you already have a rear type of porting, a couple of holes in the rear of the piston may be helpful. Holes in the piston aid in lubrication & cylinder cooling.

A DH type of boost port jig has been working for me for many years. Most of you folks are too young to know about Dale Herbrandson Reed Valves.

400 CZ DH reed

Reed conversion with rear boost ports.

Boost porting in CR250 cylinder

Some of us Old Farts have been around since reed valves started to show up in the early 70’s
:Smoke:

2 stroke thinker

Piston port was the heads up technology til they designed the reed valve setup.
Still to this day... The Piston port is being refined by the advanced shop to the "back yard guy".
Adding a nice pipe,carb,etc... they performed rather well for what they could do performance wise.
Good Luck and if anyone has any tips and tricks, Let us know as this is a 2 stroke information highway !!

Rule #1: There’s more or less a set amount of power available for you to manipulate. If you port for high RPM power then your low/mid-range power will suffer. You are robbing Peter to pay Paul.
Rule #2: You are pretty much stuck with the porting arrangement the factory put in your cylinder. If...

Essentials to know first:
The peak power and length of powerband are mostly controlled by the design of the expansion chamber.
The engine porting determines whether high RPM or mid range RPM is where the engine harmonizes the most for the most power (relatively speaking).
The carb size favors...

My Engine Oil Summary
Fully mineral oil (petroleum oil) protects OK but only when using a generous amount of it. But using a high amount of it dirties the engine and the exhaust pipe quickly with carbon. This is definitely not good for engines with exhaust valves. But if you are after high...

Here's my assessment of the formulas proposed by Gordon Jennings way back in the early 70's. They were just beginning to investigate back then and so were starting from scratch.
Jennings main shortcomings;
0. He assumes the same temperature and sound wave speed inside all pipes.
1. Because of...